kernel/linux.git/drivers/gpu/drm/amd/display/dc/bios, branch linux-7.0.y

drm/amd/display: Validate GPIO pin LUT table size before iterating

2026-06-01T15:54:30+00:00

commit 86d2b20644b11d21fe52c596e6e922b4590a3e3f upstream. [Why&How] The GPIO pin table parsers in get_gpio_i2c_info() and bios_parser_get_gpio_pin_info() derive an element count from the VBIOS table_header.structuresize field, then iterate over gpio_pin[] entries. However, GET_IMAGE() only validates that the table header itself fits within the BIOS image. If the VBIOS reports a structuresize larger than the actual mapped data, the loop reads past the end of the BIOS image, causing an out-of-bounds read. Fix this by calling bios_get_image() to validate that the full claimed structuresize is accessible within the BIOS image before entering the loop in both functions. Assisted-by: GitHub Copilot:claude-opus-4-6 Reviewed-by: Alex Hung Signed-off-by: Harry Wentland Signed-off-by: Ivan Lipski Tested-by: Dan Wheeler Signed-off-by: Alex Deucher (cherry picked from commit ba5e95b43b773ae1bf1f66ee6b31eb774e65afe3) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Fix integer overflow in bios_get_image()

2026-06-01T15:54:30+00:00

commit cd86529ec61474a38c3837fb7823790a7c3f8cce upstream. [Why&How] The bounds check in bios_get_image() computes 'offset + size' using unsigned 32-bit arithmetic before comparing against bios_size. If a VBIOS image contains a near-UINT32_MAX offset the addition wraps to a small value, the comparison passes, and the function returns a wild pointer past the VBIOS mapping. Additionally, the comparison uses '<' (strict), which incorrectly rejects the valid exact-fit case where offset + size == bios_size. Fix both issues by restructuring the check to avoid the addition entirely: first reject if offset alone exceeds bios_size, then check size against the remaining space (bios_size - offset). This eliminates the overflow and correctly permits exact-fit accesses. Assisted-by: GitHub Copilot:claude-opus-4.6 Reviewed-by: Alex Hung Signed-off-by: Harry Wentland Signed-off-by: Ivan Lipski Tested-by: Dan Wheeler Signed-off-by: Alex Deucher (cherry picked from commit d40fb392af659c4a02b560319f226842f6ec1a95) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Read EDID from VBIOS embedded panel info

2026-05-23T11:09:34+00:00

[ Upstream commit 9ea16f64189bf7b6ba50fc7f0325b3c1f836d105 ] Some board manufacturers hardcode the EDID for the embedded panel in the VBIOS. This EDID should be used when the panel doesn't have a DDC. For reference, see the legacy non-DC display code: amdgpu_atombios_encoder_get_lcd_info() This is necessary to support embedded connectors without DDC. Fixes: 4562236b3bc0 ("drm/amd/dc: Add dc display driver (v2)") Link: https://gitlab.freedesktop.org/drm/amd/-/work_items/5192 Signed-off-by: Timur Kristóf Signed-off-by: Alex Deucher (cherry picked from commit eb105e63b474c11ef6a84a1c6b18100d851ff364) Signed-off-by: Sasha Levin

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

drm/amd/display: Initialize DAC in DCE link encoder using VBIOS

2026-02-19T17:16:12+00:00

The VBIOS DAC1EncoderControl() function can initialize the DAC, by writing board-specific values to certain registers. Call this at link encoder hardware initialization time similarly to how the equivalent UNIPHYTransmitterControl initialization is done. This fixes DAC output on the Radeon HD 7790. Also remove the ENCODER_CONTROL_SETUP enum from the dac_encoder_control_prepare_params function which is actually not a supported operation for DAC encoders. Fixes: 0fbe321a93ce ("drm/amd/display: Implement DCE analog link encoders (v2)") Signed-off-by: Timur Kristóf Tested-by: Mauro Rossi Suggested-by: Alex Deucher Reviewed-by: Alex Hung Signed-off-by: Alex Deucher

drm/amd/display: Add missing encoder setup to DACnEncoderControl

2026-01-05T22:00:00+00:00

Apparently the DAC encoder needs to be set up before use. The BIOS parser in DC did not support this so I assumed it was not necessary, but the DAC doesn't work without it on some GPUs. Fixes: 69b29b894660 ("drm/amd/display: Hook up DAC to bios_parser_encoder_control") Reviewed-by: Alex Deucher Signed-off-by: Timur Kristóf Signed-off-by: Alex Deucher

drm/amd/display: Correct color depth for SelectCRTC_Source

2026-01-05T22:00:00+00:00

Pass the correct enum values as expected by the VBIOS. Previously the actual bit depth integer value was passed, which was a mistake. Fixes: 7fb4f254c8eb ("drm/amd/display: Add SelectCRTC_Source to BIOS parser") Reviewed-by: Alex Deucher Signed-off-by: Timur Kristóf Signed-off-by: Alex Deucher

drm/amd/display: Check ATOM_DEVICE_CRT2_SUPPORT in dc_load_detection

2025-11-26T16:35:22+00:00

[WHY & HOW] Fix the typo of the else-if condition from ATOM_DEVICE_CRT1_SUPPORT to ATOM_DEVICE_CRT2_SUPPORT. Reviewed-by: Harry Wentland Signed-off-by: Ivan Lipski Signed-off-by: Alex Hung Tested-by: Dan Wheeler Signed-off-by: Alex Deucher

drm/amd/display: Fix logical vs bitwise bug in get_embedded_panel_info_v2_1()

2025-11-26T16:29:08+00:00

The .H_SYNC_POLARITY and .V_SYNC_POLARITY variables are 1 bit bitfields of a u32. The ATOM_HSYNC_POLARITY define is 0x2 and the ATOM_VSYNC_POLARITY is 0x4. When we do a bitwise negate of 0, 2, or 4 then the last bit is always 1 so this code always sets .H_SYNC_POLARITY and .V_SYNC_POLARITY to true. This code is instead intended to check if the ATOM_HSYNC_POLARITY or ATOM_VSYNC_POLARITY flags are set and reverse the result. In other words, it's supposed to be a logical negate instead of a bitwise negate. Fixes: ae79c310b1a6 ("drm/amd/display: Add DCE12 bios parser support") Signed-off-by: Dan Carpenter Reviewed-by: Alex Hung Signed-off-by: Alex Deucher